This invention relates to a vision tester, in general, and, more particularly, to a device for use by a consumer in testing his near vision to determine the strength of non-prescription reading glasses the consumer requires.
It is now a common practice to sell non-prescription reading glasses directly to the consumer at pharmacies and other retail outlets. The non-prescription reading glasses are displayed in a retail establishment on free-standing displays.
Typically, a consumer selects a pair of non-prescription reading glasses from the display by trying on a number of pairs until he locates a pair that is suitable, from the standpoint of comfort, magnifying ability and appearance. In order to determine the appropriate magnifying ability for the reading glasses, charts are placed on the displays for the reading glasses. The charts have increasing sizes of print, and the purchaser of the reading glasses is instructed to stand approximately 14 inches (35.6 cm.) from the chart. When viewing the chart, the consumer will look at each line of print, and note the first line of print that appears to be out of focus. By reading across the chart, the consumer can then determine the amount of magnification needed for the reading glasses. The amount is expressed in diopters, an optical unit of measurement.
Once the consumer determines the appropriate amount of magnification needed, the consumer will then view all of the glasses on the display rack that have lenses at the appropriate diopter rating. The consumer can then select a pair of reading glasses which the consumer finds to be attractive and comfortable.
Although the use of the charts can effectively determine the proper amount of magnification needed for the reading glasses, it has been found that the use of the charts is imprecise. Quite often, the consumer will not stand an appropriate distance from the chart and, accordingly, consumers test the reading glasses by simply trying on a large number of reading glasses, of different magnifications, and testing them in connection with reading matter that is hand held by the consumer. The consumer will not always replace the reading glasses that have been tried on in the proper place on the display rack, and eventually, the reading glasses on the display rack are in total disarray.
A vision tester that has overcome the foregoing problems is disclosed in U.S. Pat. No. 5,861,941, the disclosure of which is incorporated by reference herein. Applicant is one of the co-inventors of the invention disclosed in that patent.
The device disclosed in U.S. Pat. No. 5,861,941 precisely measures the magnification power necessary for the reading glasses of each consumer. By utilizing the device, the consumer can accurately determine the appropriate diopter rating for the reading glasses, and try on only those reading glasses having that diopter rating. Since the reading glasses will be removed from only one segment of the display holding reading glasses, there is a much greater probability that the reading glasses will be returned to that segment after they are tried on, if they are not purchased.
Another advantage of the prior invention is that it is formed as part of a display rack for non-prescription reading glasses. This permits the consumer to test her vision at the same location as the location of the non-prescription reading glasses. Since the vision tester is formed as part of the display rack, there is little likelihood of damage caused by dropping or mishandling the vision tester.
The device of the instant invention enjoys all of the advantages of the invention covered by the prior patent. However, it also enjoys certain advantages over the prior invention.
In the prior invention, the distance between the reading material and the lenses used to test the near vision of the consumer was approximately 14 inches (35.6 cm.). That distance could easily be accommodated on a large display rack, such as the type shown in U.S. Pat. No. 5,861,941. However, in certain low-volume stores or in stores that do not have the floor space readily available to accommodate a large display rack, a smaller display rack that is placeable at the end of shelving is used. The smaller display rack can have a depth that is significantly less than 14 inches (35.6 cm.). The vision tester of the instant invention can be effectively used on display racks that have a depth that is significantly smaller than 14 inches (35.6 cm.).
Another advantage of the instant invention is that the light in the ceiling of a store projects directly on the printed material used for testing the vision. In the device covered by U.S. Pat. No. 5,861,941, ceiling light illuminated the printed material only indirectly, that is, the ceiling light projected downwardly and parallel to the printed material. Accordingly, in the instant invention, greater illumination of the printed material is obtained.
A third advantage of the instant invention is that the ceiling light, in passing through the printed material, strikes a mirror that is placed at an obtuse angle within the tester. The light from the ceiling strikes the mirror and passes through the eye holes containing the lenses for testing vision. The light projecting through the eye holes is visible to consumers walking by the display, and tends to attract consumers to the display.